Calculating machine



March 15, 1938. w. ARNETT 2,111,349

CALCULATING MACHINE Filed Aug. 10, 1936 2 Sheets-Sheet l March 15, 1938.

- W. ARNETT CALCULATING MACHINE Filed Aug. 10, 1936 lO's FEET FEET INCHE 5 5|XTEENTH'5 War/i Ameff Maw:

2 Sheets-Sheet 2 Patented Mar. 15, 1938 UNITED STATES PATENT OFFIQECALCULATING MACHINE Worth Arnett, Birmingham, Ala.

Application August 10, 1936, Serial No. 95,221

1 Claim.

This invention relates to a calculating machine and more particularly toan adding or subtracting machine of the type comprising a series ofrotary indicating dials or discs adapted to be acted upon by a suitabletool such as a stylus, pencil or the like to actuate the computingmechanism.

The principal object of this invention is to pro vide between the dialsor discs of the calculating machine each carrying a different memberscale, an indicating member provided with a visible portion which isbrought into view over a dial having a number scale of one characterwhen an adjacent dial having a number scale of a diiferent character isgiven a complete revolution so as to indicate to the operator when tocarry or borrow depending upon whether the machine is operated foraddition or subtraction.

Another object of this invention is to enable the zero position to bequickly and readily obtained in resetting the mechanism and withpractically no mental effort on the part of the operator.

A further object of this invention relates to the adaptability of thesame for use in computations of varying character wherein the dials maybe formed to read in hours, days, weeks, months and years; fractions ofan inch, inches, feet, yards, etc. or any other number system adaptablefor addition or subtraction.

A still further object of this invention relates to the simpleconstruction of the same which is of relatively few parts, inexpensiveto manufacture, which may be made small in size for carrying in apocket, and which is accurate and dependable in operation.

Other objects of this invention will become apparent as the descriptionthereof given hereunder proceeds with reference to the accompanyingdrawings wherein:-

Figure 1 is a top plan View of the calculating machine.

Figure 2 is a plan view of the interior of the calculating machine withthe cover removed.

Figure 3 is a transverse sectional view taken on line 3-3, Figure 1,looking in the direction of the arrows.

Figure 4 is a plan view of a modified form of calculating machine.

Figure 5 is a detail sectional view of one end of the indicating membertaken on line 55, Figure 2.

Referring to the several figures of the drawings, in which correspondingparts are indicated by the same reference characters, l0 indicates acasing housing the computing mechanism which comprises see Figure 3, abase H, a spacer l2 and a cover l3; made of any suitable rigid materialsuch as sheet metal, fibre, cardboard, Bakelite, etc. The spacer I2 isof the same outside dimensions as the base H and is in the form of agasket having long sides l4 and I5, and short sides if: and H, asclearly shown in Figure 2, and defines a walled recess.

Arranged in a row on the base H and symmetrically spaced from the sidesof the spacer 52 are a plurality of rotatable number dials 2i 2%, 22 and23, each fitted on a sleeve 2 centered by an internally threaded pin 25projecting upwardly through the base II. The sleeves 24 are preferablymade of a length exceeding the thickness of the dials 20, 2i, 22 and 23so as to project slightly above the same for a purpose to be hereinafterdescribed. As the construction of the parts for each dial is identical,a descrip tion of the same with reference to the dial 29 shown insection in Figure 3 will be given.

Mounted on the projecting fall of the sleeve 24 is a stationary numberdial 26c having a diameter less than the diameter of the dial iii, bothsaid dials being co-axially arranged. The dial 28a is securely clampedto the sleeve 26 and base it by the screw 28 having threaded engagementwith the pin 25. Similar stationary dials Zia, 22a and 23a, arerespectively mounted in a like manner in superposed relation to therotary dials 2i, 22, and 23.

Each of the rotating dials 20, 2!, 22 and 23 is provided with a circularrow of ten equally spaced openings 30 adjacent the peripheral edgethereof, numbered from 0 to 9 in a clockwise direction in the manner asshown in Figure 2. Opposite the numeral 9 on each rotating dial there isprovided thereon a cam projection or lug 3| that extends radiallyoutwardly from the periphery of the dial. For each rotating dial thereis provided in the base ii an opening 32, each in a plane normal to theline passing through the centers of rotation of the dials 28, 2|, 22 and23 and so positioned as to register with the openings 36 in said dials.Thus with the zero opening of each dial brought into registry with theopening 32 all of said dials will be set in their zero positionpreliminary to operating the machine in the manner to be hereinafterdescribed.

The stationary dials 20a, 2m, 22a and 2311 are numbered in acounter-clockwise direction from 1 to 9 with the zero position indicatedby a cut-away or notched portion 34 formed on said dials. The cut-awayportions 34 are made large enough so that the numerals on the rotatingdials will clearly appear therein, see Figure 1. As the latter dials areturned, the numerals thereon being completely covered by said stationarydials except as above indicated, the stationary dials 20a, 2|a, 22a and230, are positioned in an identical manner with the cut-away portions 34arranged in opposed relation to the openings 32 in the base Pivotallyarranged for oscillating movement between the rotating dials areindicators 36, 31 and 38. The indicators are preferably formed of verythin sheet metal having a body portion 39 provided at one end with asemi-circular flanged abutment 40 and at its other end with a raised oroffset indicating extension 4| of any suitable shape which may in orderto increase its visibility be given any desired color. The indicators36, 31 and 38 are arranged in line between the rotating dials, seeFigure 2, and are pivotally attached to the base I by the screws 42. Inorder to prevent the indicators from getting out of position the spacerl2 on its long side I4 is provided with integral tongues or guides 44and 45, with the guides 44 being of greater length than the guides 45.Thus with the indicators attached to the base H the spacer I2 is soarranged that the long guides 44 will extend beneath the raisedindicating extensions 4| while the short guides 45 will extend over thebody portions 39.

Referring to Figure 2 it will be observed that the indicators are soformed that in their normal position relative to the rotating dials, theabutment 49 will ride substantially on the periphery of the rotatingdial adjacent thereto while the indicating extension 4| willsubstantially clear the rotating dial adjacent thereto to be completelyhidden beneath the cover l3 as will be hereinafter described.

The cover plate i3 is provided with a row of circular openings 20b, 2|b,22b and 23b of a diameter slightly less than the diameter of therotating dials whereby when the cover 3 is applied the openings 30 insaid dials will appear in a circular row between the peripheral edge ofsaid openings and the peripheral edge of the stationary dials, asclearly shown in Figure 1. Around each of said openings is provided acircular row of numerals from 0 to 9 in aclockwise direction with thezero of each row opposite the cutaway portion 34 of the stationarydials.

The base spacer l2 and cover i3 are maintained in assembled relation bythe screws 48. Referring to Figure 3 it will be observed that for thesake of clarity there is shown a space between the spacer l2 and cover|3 in actual practice in View of the thinness of the same and theindicators the edges of the spacer and cover are actually broughttogether by the screws 48.

To add, for example numbers 2165 and 3281, first with the rotating dialsall in the zero setting, dial 2165 by placing a pencil or stylus in theopening of the dial 20 opposite the numeral 2 and turn the samecounterclockwise until the pencil engages opening 32 in base Similarlydial 1, 6, and 5 respectively on dials 2|, 22 and 23. Then 2--165 willshow in openings or cut-away portions 34 of the stationary dials. Nextdial 3281 in a similar manner. Now 5346 will show in openings 34, withindicating extension 4| showing above the numeral 3. Place pencil inopening opposite 1 to right of indicator and turn dial 2|counterclockwise till pencil engages base opening 32. This forcesindicating extension 4| out of View and the sum of 2165 and 3281 isshown to be 5446.

For adding numerals on cover are used with rotating dials turnedcounterclockwise always carrying when indicated in the manner asdescribed above. To subtract use the numerals on the stationary dialsand turn the rotating dials clockwise, borrowing when the indicatorsshow. Both borrowing and carrying should be done in the order of tens,hundreds, thousands.

The calculating machine shown in the mod"- fication of Figure 4 isconstructed on the same principles as above set forth and is calibratedto give readings in feet, inches and fractions of an inch. Thus therotating dial A gives readings in feet in increments of ten, the dial Bgives readings in feet from 1 to 9, the dial C gives readings in inchesfrom 1 to 11, and the dial D gives readings in sixteenths of an inchfrom 1 3' to {-2, each dial being provided with the corresponding numberof openings and numerals in the manner shown. The dial settings as shownin Figure 1 gives a reading of 541 Addition and subtraction in feet andinches is accomplished in the same manner as described above.

Having thus set forth and disclosed the nature of this invention, whatis claimed is:

In an adding and subtracting machine including a casing having a base,sides, and a cover provided with a plurality of circular openings, apair of superposed dials arranged concentrically with respect to eachcover opening and mounted on the base of said casing, the lower dial ofeach pair being rotatable and stylus operated and the upper dial beingstationary, of less diameter than the lower dial and said circularopening and in the plane of said opening to define therewith an annularopening; the combination of an indicator member disposed between eachtwo adjacent rotary dials, each indicator member comprising a bodyportion pivoted to the base of said casing, an abutment at one end ofsaid body portion arranged in juxtaposition to an adjacent rotary dial,and a laterally ofiset indicating PS1"- tion at the other end thereofarranged to be moved within said annular space across the other adjacentrotary dial, each rotary dial being provided with a cam lug adapted toengage the abutment of an adjacent indicator member to actuate the same,said indicator members being arranged on the same side of said dials andadjacent side of said casing and a pair of guide members of unequallength for each indicator member to said casing side and extendinglaterally across said indicator members, the shorter of said guidemembers engaging the upper surface of said body portions and the longerof said guide members engaging the under surface of said indicatingportion.

WORTH ARNE'IT.

